An Indian rocket carrying communication satellite successfully lifted off from the Sriharikota spaceport here Sunday.

The Rs.365 crore launch mission has twin purpose - to flight test the cryogenic engine designed and built by the Indian Space Research Organisation (ISRO), and to put in orbit communication satellite GSAT-14.

Precisely at 4.18 pm, the Geosynchronous Satellite Launch Vehicle-Development 5 (GSLV D5) with a deep roar rose into sky with a thick orange flame at its tail, breaking away from the second launch pad here at the Satish Dhawan Space Centre.

The 49.13-metre tall rocket weighing 414.75 tonnes is expected to sling the 1,982 kg GSAT-14 in the intended orbit around 17 minutes into the flight.

The Indian Space Research Organisation (ISRO) was to launch this rocket last August but aborted the mission just hours before the deadline as the fuel started leaking from its second stage or engine.

ISRO scientists at the mission control centre here watched their monitors intently to see the rocket's progress.

A cryogenic engine is more efficient as it provides more thrust for every kilogram of propellant burnt.

This was the first mission of GSLV during the last four years after two such rockets failed in 2010.

One of the GSLV rockets was launched with Indian cryogenic engine and the other one with a Russian engine.

The GSLV is a three stage/engine rocket. The core of first stage is fired with solid fuel while the four strap-on motors by liquid fuel. The second is the liquid fuel and the third is the cryogenic engine.

For the country, ISRO perfecting the cryogenic engine technology is crucial as by launching communication satellites by itself it can help save precious foreign exchange.

ISRO chairman K. Radhakrishnan has told IANS that the country pays around $85-90 million or around Rs.500 crore as launch fee for sending up a 3.5-tonne communication satellite. The cost of satellite is separate.

He said the cost of GSLV is Rs.220 crore.

The ISRO can send smaller communication satellites - weighing around two tonnes - till such time it gets ready an advanced GSLV variant - GSLV-Mark III - that can lug satellites weighing around four tonnes.

After the last launch attempt failed, Isro engineers worked tirelessly to redesign the launcher’s liquid hydrogen-fuelled second stage. They seem to be leaving nothing to chance this time round, swarming all over the launcher with technical toothcombs to ensure an uninterrupted countdown and liftoff.

The most important objective of the GSLV-D5 mission, however, is to flight-test the rocket’s all-important third stage: the indigenously-built cryogenic upper stage (CUS). The CUS, expected to be the mainstay of future GSLV flights, replaces the Russian cryogenic engine which was used in the rocket’s earlier experimental flights.

The GSLV’s significance lies in the fact that the future of the global satellite market lies in the field of communications. The GSAT 14 satellite piggybacking the GSLV-D5 carries six Ku-band and six extended C-band transponders to help in digital audio broadcasting and other communications across the entire subcontinent.

Designed to last for a dozen years in its orbit, the satellite will replace the GSAT-3 (EDUSAT) which has been in orbit for 10 years.

The big boosters in the GSLV series can hoist heavy communication satellites into geosynchronous orbits 36,000 km above the equator. In this position, the satellite keeps pace with Earth’s rotation and, as a result, appears stationary from the ground.

This makes it easier to build simpler antennas on the ground, which do not have to track moving satellites in the sky.

These engines use fuels like oxygen and hydrogen in liquid form — stored at extremely low temperatures — to produce enormous amounts of thrust per unit mass (engineering parlance for the mass of fuel the engine requires to provide maximum thrust for a specific period such as, say, pounds of fuel per hour per pound of thrust).

Rockets powered by cryogenic motors, therefore, need to carry much less fuel than would otherwise be required. Cryogenic fuels are also extremely clean as they give out only water while burning. A successful GSLV-D5 flight will make India only the sixth nation to possess this cutting edge technology, joining the United States, Russia, France, Japan and China in an elite club.

India’s cryogenic motor development encountered some rough weather in 1993 when exaggerated US jitters — that India might utilise its space capabilities for military purposes — led to Moscow chickening out of a cryo-engine technology transfer deal with New Delhi.

Of course, the real reason for guarding cryogenic engine technology so zealously probably had more to do with economics than national security. India’s arrival in the global heavy-lift launch market as a low cost launch source would have threatened the business interests of Europe, Russia, and the US.

In hindsight, though, it seems to have been a disguised blessing for Indian scientists who were forced to develop the technology on their own.

The GSLV will reduce India’s dependence on foreign launchers like the ESA’s Ariane to launch INSAT-class satellites.

Isro sources speak of plans to fly two more GSLVs at six-month-intervals before using the third one for the Chandrayaan-2 Moon mission. The GSLV-Mark III is also earmarked for launching human space flights in future and building orbiting space stations.

Isro has built up an impressive portfolio of comparatively cheap space products and services that are attractive to foreign space agencies that want to outsource space missions